Display device

ABSTRACT

A display device includes a display member and a touch member. The display member is configured to generate an image. The display member includes a folding area configured to be folded along a folding axis, and another area adjacent to the folding area. The touch member is configured to detect a touch interaction association with the display member. The touch member includes a touch sensor, and a signal line electrically connected to the touch sensor. The touch sensor is a mesh-shaped touch sensor. A mesh line of the mesh-shaped touch sensor crosses the folding axis. A minimum angle between the folding axis and the mesh line is less than 90 degrees.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. patent application Ser. No.14/989,435, filed Jan. 6, 2016, which issued as U.S. Pat. No.10,901,541, which claims priority to and the benefit of Korean PatentApplication No. 10-2015-0023580, filed Feb. 16, 2015, each of which isincorporated by reference for all purposes as if fully set forth herein.

BACKGROUND Field

Exemplary embodiments relate to a display device. More particularly,exemplary embodiments relate to a foldable display device.

Discussion

A display device displays various images on a display screen to providea user with information. Foldable display devices including flexibledisplay members have also been developed. Additionally, these displaydevices may include a touch member, which may be folded to correspond tothe flexible display member. The touch member may determine coordinateinformation of a position at which a touch event occurs, as well asprovide information to the display member. The display member may beconnected to the touch member and display an image corresponding to theinformation provided by the touch member. It is noted, however, that afoldable display device may be folded, rolled, twisted, etc., whereas aflat panel display device is not designed to withstand suchmanipulation. To this end, a foldable display device, which may bedeformed in various shapes, may be more portable and more user friendlythan a typical flat panel display device.

The above information disclosed in this Background section is only forenhancement of understanding of the background of the inventive concept,and, therefore, it may contain information that does not form the priorart that is already known in this country to a person of ordinary skillin the art.

SUMMARY

Exemplary embodiments provide a display device including a touch memberwith improved reliability.

Additional aspects will be set forth in the detailed description whichfollows, and, in part, will be apparent from the disclosure, or may belearned by practice of the inventive concept.

According to one or more exemplary embodiments, a display deviceincludes a display member and a touch member. The display member isconfigured to generate an image. The display member includes a foldingarea configured to be folded along a folding axis, and another areaadjacent to the folding area. The touch member is configured to detect atouch interaction association with the display member. The touch memberincludes a touch sensor, and a signal line electrically connected to thetouch sensor. The touch sensor is a mesh-shaped touch sensor. A meshline of the mesh-shaped touch sensor crosses the folding axis. A minimumangle between the folding axis and the mesh line is less than 90degrees.

According to one or more exemplary embodiments, when the touch member isfolded along the folding axis, stress applied to the mesh lineoverlapping the folding area is reduced at least because the mesh lineis not perpendicular to the folding axis. As such, damage associatedwith bending stress applied to the mesh line is prevented or at leastreduced. To this end, reliability of the touch member is improved.

The foregoing general description and the following detailed descriptionare exemplary and explanatory and are intended to provide furtherexplanation of the claimed subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the inventive concept, and are incorporated in andconstitute a part of this specification, illustrate exemplaryembodiments of the inventive concept, and, together with thedescription, serve to explain principles of the inventive concept.

FIGS. 1A, 1B, and 1C are perspective views of a display device,according to one or more exemplary embodiments.

FIG. 2 is an equivalent circuit diagram of a pixel of a display member,according to one or more exemplary embodiments.

FIGS. 3A, 3B, and 3C are side views of a display device, according toone or more exemplary embodiments.

FIG. 4 is a plan view of a touch member, according to one or moreexemplary embodiments.

FIG. 5A is an enlarged plan view of portion AA′ in FIG. 4, according toone or more exemplary embodiments.

FIG. 5B is an enlarged plan view of portion BB′ of FIG. 4, according toone or more exemplary embodiments.

FIG. 6A is a plan view of a touch member, according to one or moreexemplary embodiments.

FIG. 6B is an enlarged plan of portion CC′ of FIG. 6A, according to oneor more embodiments.

FIGS. 7A and 7B are graphs demonstrating a variation in resistance of atouch member as a function of the number of times the touch member isfolded, according to one or more exemplary embodiments.

FIGS. 8A and 8B are plan views of touch members, according to variousexemplary embodiments.

FIGS. 9A and 9B are cross-sectional views of display devices, accordingto various exemplary embodiments.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

In the following description, for the purposes of explanation, numerousspecific details are set forth in order to provide a thoroughunderstanding of various exemplary embodiments. It is apparent, however,that various exemplary embodiments may be practiced without thesespecific details or with one or more equivalent arrangements. In otherinstances, well-known structures and devices are shown in block diagramform in order to avoid unnecessarily obscuring various exemplaryembodiments.

In the accompanying figures, the size and relative sizes of layers,films, panels, regions, etc., may be exaggerated for clarity anddescriptive purposes. Also, like reference numerals denote likeelements.

When an element or layer is referred to as being “on,” “connected to,”or “coupled to” another element or layer, it may be directly on,connected to, or coupled to the other element or layer or interveningelements or layers may be present. When, however, an element or layer isreferred to as being “directly on,” “directly connected to,” or“directly coupled to” another element or layer, there are no interveningelements or layers present. For the purposes of this disclosure, “atleast one of X, Y, and Z” and “at least one selected from the groupconsisting of X, Y, and Z” may be construed as X only, Y only, Z only,or any combination of two or more of X, Y, and Z, such as, for instance,XYZ, XYY, YZ, and ZZ. Like numbers refer to like elements throughout. Asused herein, the term “and/or” includes any and all combinations of oneor more of the associated listed items.

Although the terms “first,” “second,” etc. may be used herein todescribe various elements, components, regions, layers, and/or sections,these elements, components, regions, layers, and/or sections should notbe limited by these terms. These terms are used to distinguish oneelement, component, region, layer, and/or section from another element,component, region, layer, and/or section. Thus, a first element,component, region, layer, and/or section discussed below could be termeda second element, component, region, layer, and/or section withoutdeparting from the teachings of the present disclosure.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,”“upper,” and the like, may be used herein for descriptive purposes, and,thereby, to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the drawings. Spatiallyrelative terms are intended to encompass different orientations of anapparatus in use, operation, and/or manufacture in addition to theorientation depicted in the drawings. For example, if the apparatus inthe drawings is turned over, elements described as “below” or “beneath”other elements or features would then be oriented “above” the otherelements or features. Thus, the exemplary term “below” can encompassboth an orientation of above and below. Furthermore, the apparatus maybe otherwise oriented (e.g., rotated 90 degrees or at otherorientations), and, as such, the spatially relative descriptors usedherein interpreted accordingly.

The terminology used herein is for the purpose of describing particularembodiments and is not intended to be limiting. As used herein, thesingular forms, “a,” “an,” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise. Moreover,the terms “comprises,” “comprising,” “includes,” and/or “including,”when used in this specification, specify the presence of statedfeatures, integers, steps, operations, elements, components, and/orgroups thereof, but do not preclude the presence or addition of one ormore other features, integers, steps, operations, elements, components,and/or groups thereof.

Various exemplary embodiments are described herein with reference tosectional illustrations that are schematic illustrations of idealizedexemplary embodiments and/or intermediate structures. As such,variations from the shapes of the illustrations as a result, forexample, of manufacturing techniques and/or tolerances, are to beexpected. Thus, exemplary embodiments disclosed herein should not beconstrued as limited to the particular illustrated shapes of regions,but are to include deviations in shapes that result from, for instance,manufacturing. For example, an implanted region illustrated as arectangle will, typically, have rounded or curved features and/or agradient of implant concentration at its edges rather than a binarychange from implanted to non-implanted region. Likewise, a buried regionformed by implantation may result in some implantation in the regionbetween the buried region and the surface through which the implantationtakes place. Thus, the regions illustrated in the drawings are schematicin nature and their shapes are not intended to illustrate the actualshape of a region of a device and are not intended to be limiting.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this disclosure is a part. Terms,such as those defined in commonly used dictionaries, should beinterpreted as having a meaning that is consistent with their meaning inthe context of the relevant art and will not be interpreted in anidealized or overly formal sense, unless expressly so defined herein.

FIGS. 1A, 1B, and 1C are perspective views of a display device,according to one or more exemplary embodiments. FIG. 1A is a perspectiveview of display device 100 in an unfolded state, FIG. 1B is aperspective view of display device 100 in a first folded state, e.g., an“inwardly” folded state, and FIG. 1C is a perspective view of displaydevice 100 in a second folded state, e.g., an “outwardly” folded state.FIG. 2 is an equivalent circuit diagram of a pixel of a display member,according to one or more exemplary embodiments.

As seen in FIGS. 1A to 1C, the display device 100 includes a displaymember 10 and a touch member 20. The display device 100 includes anactive region AR and a non-active region NAR. In an unfolded state, theactive region AR and the non-active region NAR may be disposed in aplane defined by a first direction DR1 and a second direction DR2. Theactive region AR is a region in which the touch member 20 may beactivated, e.g., a region in which touch interactions (near and/or closetouches) may be detected. The active region AR may also correspond to adisplay region (not shown) in which the display member 10 may beactivated, e.g., a region in which images may be displayed. As such, theactive region AR and the display region may overlap one another. In thismanner, a user may input a touch signal to the display device andsimultaneously (or substantially simultaneously) perceive informationfrom an image displayed via the display region. The non-active regionNAR is disposed outside the active region AR, and, to this end, may be aregion in which the touch member 20 is inactivated. For example, thenon-active region NAR may include lines to transmit electrical signalsthat activate and/or deactivate the active region AR.

The display member 10 may display images. Although not illustrated, thedisplay member 10 may include a plurality of data lines, a plurality ofscan lines, and a plurality of pixels connected to corresponding datalines and corresponding scan lines. The pixels may be arranged in anysuitable formation (e.g., a matrix formation) when viewed in a planview. A pixel may be turned on or turned off in response to a scansignal provided via a corresponding scan line. The pixel may alsogenerate light (e.g., display an image) corresponding to a data signalprovided via a corresponding data line. An exemplary pixel structurewill be described in more detail in association with FIG. 2.

FIG. 2 is an equivalent circuit diagram of a representative pixel PXijconnected to an i-th scan line SLi and a j-th data line Dj among pixelsof display device 100. In this manner, other pixels of display device100 may have the same equivalent circuit diagram as the pixel PXij. Assuch, duplicative descriptions have been omitted to avoid obscuringexemplary embodiments described herein.

Referring to FIG. 2, the pixel PXij may include at least one thin filmtransistor, at least one capacitor, and at least one light emittingelement. For example, the pixel PXij includes a first thin filmtransistor TFT1, a second thin film transistor TFT2, a capacitor Cap,and an organic light emitting diode OLED.

The first thin film transistor TFT1 includes a control electrodeconnected to the i-th scan line SLi, a first (e.g., input) electrodeconnected to the j-th data line DLj, and a second (e.g., output)electrode connect to a first capacitor electrode of the capacitor Cap.In this manner, the first thin film transistor TFT1 may output a datasignal provided via the j-th data line DLj in response to a scan signalprovided via the i-th scan line SLi. The capacitor Cap includes a firstcapacitor electrode connected to the second electrode of the first thinfilm transistor TFT1 and a second capacitor electrode configured toreceive a first source voltage ELVDD. The capacitor Cap may be chargedaccording to a difference in voltage between a voltage output via thefirst thin film transistor TFT1 and the first source voltage ELVDD.

The second thin film transistor TFT2 includes a control electrodeconnected between the second electrode of the first thin film transistorTFT1 and the first capacitor electrode of the capacitor Cap, a first(e.g., input) electrode configured to receive the first source voltageELVDD, and a third (e.g., output) electrode. The third electrode of thesecond thin film transistor TFT2 is connected to the organic lightemitting diode OLED. In this manner, the second thin film transistorTFT2 may control a driving current through the organic light emittingdiode OLED in response to an amount of electric charge charged storedvia the capacitor Cap. A turn-on time period of the second thin filmtransistor TFT2 may be determined according to the amount of electriccharge stored via the capacitor Cap. The third electrode of the secondthin film transistor TFT2 may apply a voltage having a lower voltagelevel than the voltage level of the first source voltage ELVDD to theorganic light emitting diode OLED.

The organic light emitting diode OLED includes a first electrodeconnected to the third electrode of the second thin film transistor TFT2and a second electrode configured to receive a second source voltageELVSS. Although not illustrated, the organic light emitting diode OLEDmay include a light emitting pattern disposed between the firstelectrode and the second electrode. In this manner, the organic lightemitting diode OLED may emit light during the turn-on time period of thesecond thin film transistor TFT2. Light emitted from the organic lightemitting diode OLED may have a color determined according to a materialof the light emitting pattern. For instance, the color of the lightemitted from the organic light emitting diode OLED may be a red, green,blue, or white color. It is contemplated, however, that the organiclight emitting diode OLED may be configured to emit any suitable colorof light. To this end, it is also contemplated that the light emittingdiode OLED may be configured to emit different colors based on differentapplied voltage/current. In other words, the light emitting diode may be“color tunable” via, for instance, different electroluminescentmolecules, one or more stacks of different light-emitting layers ofdifferent emissive colors, etc.

Adverting back to FIGS. 1A to 1C, the display member 10 may be flexed,e.g., bent, rolled, folded, twisted, etc., which will be collectivelyreferred to herein as “folded.” As such, the display member 10 may befolded in various directions with respect to, for example, a foldingaxis FX. For instance, as shown in FIG. 1B, a portion of the displaymember 10 is folded along the folding axis FX and disposed above anotherportion of the display member 10 in a third direction DR3. The foldedstate in FIG. 1B may be referred to as an “inwardly” folded state, as afirst surface of display device 100 may be folded upon itself, such thatopposing portions of the first surface face one another. As anotherexample, as shown in FIG. 1C, a portion of the display member 10 isfolded along the folding axis FX and disposed under the other portion ofthe display member 10 in the third direction DR3. The folded state inFIG. 1C may be referred to as an “outwardly” folded state, as the firstsurface of the display device 100 may be folded upon itself, such thatopposing portions of the first surface face away from one another.Although not shown, it is also contemplated that the display member 10may be folded along two or more folding axes.

According to one or more exemplary embodiments, the touch member 20 isdisposed on the display member 10. The touch member 20 may sense (orotherwise detect) a touch interaction (e.g., actual touch, near touch,multiple touches, etc.) associated with the display member 10. In thismanner, a touch signal may be generated in association with touchelectrodes (not shown) of the touch member 20. As seen in FIG. 1, thetouch member 20 is disposed above the display member 10 to sense a touchsignal input to an upper portion of the display member 10. It is alsocontemplated that the touch member 20 may be disposed under, inside, orpart of the display member 10. Further, the touch member 20 may bedisposed at various positions to sense a touch signal input to thedisplay member 10. In this manner, the touch member 20 may have variousstructures, such as an electrostatic capacitive type touch panel, aresistive layer type touch panel, an electromagnetic induction typetouch panel, etc.

The touch signal may be input to the display member 10 using variousmethods. FIGS. 1A to 1C show the touch member 20 sensing the touchsignal input via a part of a human body, e.g., a finger; however, thetouch input may be input via any suitable manner, e.g., via a stylus,etc. It is also contemplated that the touch signal may be input using anoptical type input manner, a touch type input manner, a magnetic typeinput manner, etc.

As previously mentioned, the touch member 20 may be flexed. As such, atleast a portion of the touch member 20 may be folded along the foldingaxis FX to achieve an “inward” or “outward” folded state along thefolding axis FX, as shown in FIGS. 1B and 1C. For instance, FIGS. 1B and1C show the display device 100 in which at least a portion of thedisplay device 100 is rotated at an angle of about 180 degrees withrespect to the folding axis FX. It is contemplated, however, that anysuitable folding angle may be achieved, whether less than or greaterthan 180 degrees with respect to folding axis FX. Further, the foldedstate of the display device 100 may include a bending state in which thedisplay device 100 is rotated at a predetermined angle with respect tothe folding axis FX.

Referring to FIG. 1B, the display device 100 may be deformed in theinwardly folded state. In this manner, the touch member 20 is disposed“inside” the display device 100, and, as such, the touch member 20 maybe protected from external impacts. Referring to FIG. 1C, the displaydevice 100 may be deformed in the outwardly folded state. In thismanner, the touch member 20 is disposed “outside” the display device100, and, as such, the display device 100 may sense an external touchwhen in the outwardly folded state.

FIGS. 3A, 3B, and 3C are side views of a display device, according toone or more exemplary embodiments. FIG. 3A is a first side view of thedisplay device in an unfolded state, according to one or more exemplaryembodiments. FIGS. 3B and 3C are respective second and third side viewsof the display device in folded states, according to one or moreexemplary embodiments. That is, the first side view shows the displaydevice 100 in the unfolded state, the second side view shows the displaydevice 100 in the inwardly folded state, and the third side view showsthe display device 100 in the outwardly folded state.

Hereinafter, variations in the display device 100 according to thefolding of the display device 100 will be described with reference toFIGS. 3A to 3C. To avoid obscuring exemplary embodiments describedherein, duplicative descriptions are omitted.

The display member 10 includes a folding area FA and at least one areadisposed adjacent to the folding area, such as a plane area. Forexample, the display member 10 includes a first plane area PA1, thefolding area FA, and a second plane area PA2 that are sequentiallyarranged in the first direction DR1. The folding area FA overlaps thefolding axis FX, or, in other words, the folding axis FX is disposed inthe folding area FA. A stress occurs in the folding area FA when thedisplay member 10 is folded. To this end, the folding area FA is easilydeformed due to the stress, and, as such, the shape of the folding areaFA when the display member 10 is in the unfolding state is differentfrom the shape of the folding area FA when the display member 10 is in afolded state.

The stress caused, at least in part, by the folding of the displaymember 10 may not occur in the first plane area PA1 and second planearea PA2. As such, the shape of the first and second plane areas PA1 andPA2, when the display device 100 is in the unfolded state, may besubstantially the same as the shape of the first plane area PA1 and thesecond plane area PA2 when the display device 100 is in a folded state.In an exemplary embodiment, the first plane area PA1 and the secondplane area PA2 may be relatively more rigid than the folding area FA.

As seen in FIGS. 3A to 3C, a portion of the touch member 20corresponding to the folding area FA is hatched with oblique lines forillustrative convenience. Given that the touch member 20 is folded incorrespondence with the display member 10, a portion of the touch member20 that overlaps the folding area FA may be easily deformed due to thefolding stress.

As shown in FIG. 3B, the display device 100 is folded along the foldingaxis FX in the inwardly folded state. In this manner, the touch member20 is disposed at an inner side of the display member 10 and is moreadjacent to the folding axis FX than the display member 10. As such, atleast a compressive stress PS is applied to the folding area FA of thedisplay device 100 in the inwardly folded state. The portion of thetouch member 20 that overlaps the folding area FA is applied with thecompressive stress PS. To this end, the portion of the touch member 20that overlaps the folding area FA may undergo shrinkage deformation dueto the compressive stress PS. Further, the display device 100 may befolded at a predetermined radius of curvature RC. As a distance from thefolding axis FX decreases, the compressive stress PS applied to thedisplay member 10 or the touch member 20 increases. In this manner, thetouch member 20 may be applied with a greater compressive stress thanthe display member 10 when the display device 100 is in the inwardlyfolding state because the touch member 20 is folded “inside” the displaymember 10.

As shown in FIG. 3C, the display device 100 may be folded along thefolding axis FX to be in the outwardly folded state. In this manner, thetouch member 20 is disposed at an outer side of the display member 10and is disposed further from the folding axis than the display member10. At least a tensile stress TS is applied to the folding area FA ofthe display device 100 in the outwardly folded state. The portion of thetouch member 20 that overlaps the folding area FA is applied with thetensile stress TS. To this end, the portion of the touch member 20 thatoverlaps the folding area FA may undergo expansive deformation due tothe tensile stress TS. Further, when the display device 100 is outwardlyfolded at the same radius of curvature RC as the inwardly folded state,the tensile stress TS applied to the touch member 20 increases as adistance from the folding axis FX increases. Thus, the touch member 20may be applied with a greater tensile stress than the display member 10when the folding area FA is in the outwardly folded state.

Referring to FIGS. 3A to 3C, when the folding area FA is in theoutwardly folded state, the portion of the touch member 20 that overlapsthe folding area FA is deformed more than the portion of the touchmember 20 when the folding area FA is in the inwardly folded state. Asviewed relative to the same radius of curvature, a circumference of acircle becomes larger as a distance from a center of the circleincreases. As such, the touch member 20 is farthest from the foldingaxis FX when the folding area FA is in the outwardly folded state, andthe stress applied to the touch member 20 overlapping the folding areaFA in the outwardly folded state is larger than the stress applied tothe touch member 20 overlapping the folding area FA in the inwardlyfolded state. In this manner, the portion of the touch member 20overlapping the folding area FA may experience more deformation when thetensile stress TS is applied to the portion of the touch member 20 thanthat when the compressive stress PS is applied to the portion of thetouch member 20. This is described in detail in the proceedingparagraphs.

The touch member 20 is described in more detail in association withFIGS. 4, 5A, and 5B. FIG. 4 is a plan view of a touch member, accordingto one or more exemplary embodiments. FIG. 5A is an enlarged plan viewof portion AA′ of FIG. 4, whereas FIG. 5B is an enlarged plan view ofportion BB′ of FIG. 4.

The touch member 20 includes a touch sensor and a signal line. The touchsensor includes a first electrode TE1 and a second electrode TE2. Thesignal line includes a first line TW1 and a second line TW2. The firstelectrode TE1 and the second electrode TE2 are spaced apart from eachother in the third direction DR3 extending into and out of the page toallow an insulating layer to be disposed between the first electrode TE1and the second electrode TE2. For illustrative convenience, theinsulating layer is omitted from FIG. 4, and the second electrode TE2 isindicated by a dotted line because the second electrode TE2 is disposedon a different layer than the first electrode TE1. It is noted, however,that the insulating layer enables the first electrode TE1 to beinsulated from the second electrode TE2.

According to one or more exemplary embodiments, the first electrode TE1is disposed on the insulating layer. The first electrode TE1 includes aplurality of first touch electrodes TE1 a, TE1 b, and TE1 c. The firsttouch electrodes TE1 a, TE1 b, and TE1 c extend in the first directionDR1 and are arranged in a second direction DR2 crossing the firstdirection DR1. That is, the first touch electrodes TE1 a, TE1 b, and TE1c are spaced apart from each other in the second direction DR2. Further,the second electrode TE2 is disposed under the insulating layer. Thesecond electrode TE2 includes a plurality of second touch electrodes TE2a, TE2 b, and TE2 c. The second touch electrodes TE2 a, TE2 b, and TE2 cextend in the second direction DR2 and are arranged in the firstdirection DR1; that is, the second touch electrodes TE2 a, TE2 b, andTE2 c are spaced apart from each other in the second direction DR2.

Furthermore, the folding axis FX is defined substantially parallel tothe second direction DR2. Accordingly, each of the first touchelectrodes TE1 a, TE1 b, and TE1 c is substantially perpendicular to thefolding axis FX.

FIG. 5A shows a portion of a first touch electrode TE1 c among the firsttouch electrodes TE1 a, TE1 b, and TE1 c. As shown in FIG. 5A, the firsttouch electrode TE1 c includes a plurality of mesh lines defining a meshshape. The second touch electrodes TE2 a, TE2 b, and TE2 c and the otherfirst touch electrodes TE1 a and TE1 b may have substantially the sameshape as the first touch electrode TE1 c. As such, duplicativedescriptions have been omitted to avoid obscuring exemplary embodimentsdescribed herein.

The mesh lines include a plurality of first mesh lines MP-T1 extendingin one direction and a plurality of second mesh lines MP-T2 extending inanother direction crossing the first mesh lines MP-T1. At least one ofthe directions in which the first mesh lines MP-T1 and the second meshlines MP-T2 extend is different from the direction which the foldingaxis extends in.

Each of the first mesh lines MP-T1 and the second mesh lines MP-T2 has awidth, i.e., a line width, measured in terms of micrometers. Forinstance, each of the first mesh lines MP-T1 and the second mesh linesMP-T2 has the width of about 3000 micrometers or less. For instance,each of the first mesh lines MP-T1 and the second mesh lines MP-T2 has awidth in a range greater than or equal to about 10 micrometers and lessthan or equal to about 3000 micrometers, e.g., greater than or equal toabout 100 micrometers and less than or equal to about 2900 micrometers,for instance, greater than or equal to about 500 micrometers and lessthan or equal to about 2500 micrometers, such as greater than or equalto about 1000 micrometers and less than or equal to about 2000micrometers. Given that the first mesh lines MP-T1 and the second meshlines MP-T2 included in the first touch electrode TE1 c are micrometersin width, the patterns are not perceptible by (or substantiallyunperceivable to) the user. As such, although the display area mayoverlap the active region AR of the touch member 20, influences causedby the touch sensor and exerted on visibility of an image displayed inthe display area may be reduced.

Among angles between the folding axis FX and the first mesh lines MP-T1,a first minimum angle AGF-T1 is less than 90 degrees. In addition, amongangles between the folding axis FX and the second mesh lines MP-T2, asecond minimum angle AGF-T2 is less than 90 degrees. Since the touchmember 20 is folded along the folding axis FX, those mesh linesoverlapping the folding area FA (not shown) among the first mesh linesMP-T1 and the second mesh lines MP-T2 are applied with stress caused bythe folding of the folding area. The stress caused by the folding of thefolding area FA is strongest in a direction vertical (or substantiallyvertical) to the folding axis FX, e.g., orthogonal to the folding axisFX.

When the first mesh lines MP-T1 and the second mesh lines MP-T2 have arelatively “fine” width and thickness to improve visibility of an imagein the display area, the first mesh lines MP-T1 and the second meshlines MP-T2 may be easily damaged by the stress caused by the foldingaction. According to one or more exemplary embodiments, the first meshlines MP-T1 and the second mesh lines MP-T2 are disposed to form anangle less than 90 degrees with respect to the folding axis FX. As theangle between the folding axis FX and the first mesh lines MP-T1 and thesecond mesh lines MP-T2 approach zero (0), the stress applied to thefirst mesh lines MP-T1 and the second mesh lines MP-T2 decreases. Assuch, the configuration of the touch member 20 according to one or moreexemplary embodiments may prevent (or at least reduce) stress and damageof the first touch electrode TE1 c caused, at least in part, by thefolding of the display device 100.

As seen in FIG. 5A, the first mesh lines MP-T1 and the second mesh linesMP-T2 cross each other to define a plurality of transmission areas TAhaving various shapes. The transmission areas TA may have the same shapeas each other or at least some may have different shapes from eachother. Each transmission area TA may have a circular shape, an ovalshape, a polygonal shape, etc. In various exemplary embodiments, each ofthe transmission areas TA has a polygonal shape. The first mesh linesMP-T1 cross the second mesh lines MP-T2 in various alignment distancesand various cross angles. The shape of each of the transmission areas TAmay be varied depending on the alignment distance of the first meshlines MP-T1, the alignment distance of the second mesh lines MP-T2, andthe cross angle between the first mesh lines MP-T1 and the second meshlines MP-T2.

Each of the transmission areas TA defined by the first mesh lines MP-T1crossing the second mesh lines MP-T2 may have a lozenge shape. The firstmesh lines MP-T1 and the second mesh lines MP-T2 are arranged at regularintervals. Lozenge shape of each of the transmission areas TA includes afirst diagonal line Px and a second diagonal line Py. The first diagonalline Px extends in a direction substantially parallel to the foldingaxis FX. The second diagonal line Py crosses the first diagonal line Px.Since each of the transmission areas TA may have a lozenge shape, thesecond diagonal line Py may be substantially perpendicular to the firstdiagonal line Px, or, in other words, the second diagonal line Py may bevertical (or substantially vertical) to the folding axis FX.

The first diagonal line Px may have a length longer than a length of thesecond diagonal line Py. As such, the first minimum angle AGF-T1 betweenthe folding axis FX and the first mesh lines MP-T1 and the secondminimum angle AGF-T2 between the folding axis FX and the second meshlines MP-T2 may be in a range greater than or equal to about 0 degreesand less than or equal to about 45 degrees. As seen in FIG. 5A, each ofthe transmission areas TA has the lozenge shape elongated in adirection, e.g., a horizontal direction, substantially parallel to thefolding axis FX. Further, the touch member 20 has the mesh shapedefining the transmission areas TA each in which a length in thehorizontal direction is longer than a length in a vertical direction,and, as such, the conductive portion, e.g., the first mesh lines MP-T1and the second mesh lines MP-T2, may be prevented (or at least reduced)from being damaged by the folding action along the folding axis FX.

Adverting back to FIG. 4, the first line TW1 may be disposed on the samelayer as the first electrode TE1. The first line TW1 is provided in aplural number, e.g., first lines TW1 a, TW1 b, and TW1 c. The firstlines TW1 a, TW1 b, and TW1 c are connected to the first touchelectrodes TE1 a, TE1 b, and TE1 c, respectively. Further, the secondline TW2 is disposed on the same layer as the second electrode TE2. Thesecond line TW2 is provided in a plural number, e.g., second lines TW2a, TW2 b, and TW2 c. The second lines TW2 a, TW2 b, and TW2 c areconnected to the second touch electrodes TE2 a, TE2 b, and TE2 c.

FIG. 5B shows a portion of a second line TW2 a among the second linesTW2 a, TW2 b, and TW2 c. As shown in FIG. 5B, the second line TW2 aincludes a plurality of conductive lines, e.g., mesh lines defining amesh shape. The first lines TW1 a, TW1 b, and TW1 c and the other secondlines TW2 b and TW2 c may have substantially the same shape as thesecond line TW2 a. As such, duplicative descriptions have been omittedto avoid obscuring exemplary embodiments described herein.

The conductive lines include a plurality of first conductive lines MP-W1and a plurality of second conductive lines MP-W2. The first conductivelines MP-W1 cross the second conductive lines MP-W2. As seen in FIG. 5B,the first conductive lines MP-W1 and the second conductive lines MP-W2are arranged at regular intervals. To this end, a first minimum angleAGF-W1 between the folding axis FX and the first conductive lines MP-W1and a second minimum angle AGF-W2 between the folding axis FX and thesecond conductive lines MP-W2 is less than 90 degrees. In this manner,although the second line TW2 a extends in a direction substantiallyperpendicular to the folding axis FX, stress caused by the foldingaction and applied to the second line TW2 a may be reduced at leastbecause the first conductive lines MP-W1 and the second conductive linesMP-W2 of the second line TW2 a cross the folding axis FX at an angleless than 90 degrees.

According to one or more exemplary embodiments, the first conductivelines MP-W1 and the second conductive lines MP-W2 may be arranged in thesame shape as the first mesh lines MP-T1 and the second mesh linesMP-T2. The first conductive lines MP-W1 correspond to the first meshlines MP-T1 and the second conductive lines MP-W2 correspond to thesecond mesh lines MP-T2. In this manner, a plurality of transmissionareas TA defined by the intersection of the first conductive lines MP-W1and the second conductive lines MP-W2 includes a first diagonal line Pxand a second diagonal line Py. The first diagonal line Px may be longerthan the second diagonal line Py. The length of the first diagonal linePx and/or the second diagonal line Py may be determined to prevent (orat least reduce) the potential damage of the touch member 20 due to thefolding action along folding axis FX, as well as prevent (or at leastreduce) a touch sensitivity of the touch member 20. For instance, thelength of the first diagonal line Px may be in a range equal to orgreater than about 50 micrometers and less than or equal to about 500micrometers.

Although not shown, the second line TW2 may be disposed in an areaoutside (e.g., not overlapping) the folding axis FX. When the firstlines TW1 and the second lines TW2 do not overlap the folding axis FX,influences caused by the folding stress and applied to the signal linesmay be prevented (or at least reduced).

Adverting back to FIG. 4, the touch member 20 may further include a pad.The touch sensor receives an electrical signal (e.g., externalelectrical signal) from a source (e.g., an external source) (not shown)or provides the electrical signal to the external source through thepad. The pad includes a first pad TP1 and a second pad TP2. Each of thefirst pad TP1 and the second pad TP2 may be provided in a plural number.For instance, the first pad TP1 includes first pads TP1 a, TP1 b, andTP1 c respectively corresponding to the first lines TW1 a, TW1 b, andTW1 c, and the second pad TP1 includes second pads TP2 a, TP2 b, and TP2c respectively corresponding to the second lines TW2 a, TW2 b, and TW2c. The second pads TP2 a, TP2 b, and TP2 c may be disposed on adifferent layer from the first pads TP1 a, TP1 b, and TP1 c. It iscontemplated, however, that the second pads TP2 a, TP2 b, and TP2 c maybe disposed on the same layer as the first pads TP1 a, TP1 b, and TP1 c.Further, the second pads TP2 a, TP2 b, and TP2 c may be electricallyconnected to the second lines TW2 a, TW2 b, and TW2 c disposed on adifferent layer through separate contact holes. In this manner, thetouch sensor may be electrically connected to the external source afterpassing through a layer, and, as such, the touch sensor may berelatively easy to assemble with (or otherwise connect to) the externalsource.

FIG. 6A is a plan view of a touch member, according to one or moreexemplary embodiments. FIG. 6B is an enlarged plan view of portion CC′of FIG. 6A. The touch member of FIGS. 6A and 6B is similar to the touchmember in FIGS. 4, 5A, and 5B, and, as such, duplicative descriptionsare omitted to avoid obscuring exemplary embodiments described herein.

Referring to FIG. 6A, the touch member 20-1 may further include anadding part AP. The adding part AP overlaps the folding axis FX. Theadding part AP covers at least a portion of the folding area FA andextends adjacent to the folding area FA of a plane area, e.g., firstplane area PA1. The adding part AP forms portions of first touchelectrodes TE1 a, TE1 b, and TE1 c. The adding part AP may be furtherdisposed on portions overlapping the folding axis FX among the secondtouch electrodes TE2 a, TE2 b, and TE2 c, the first lines TW1 a, TW1 b,and TW1 c, and the second lines TW2 a, TW2 b, and TW3 c, but exemplaryembodiments are not limited thereto or thereby.

Referring to FIG. 6B, the adding part AP includes a plurality of thirdmesh lines MP-T3 and a plurality of fourth mesh lines MP-T4 crossing thethird mesh lines MP-T3. The third mesh lines MP-T3 and the fourth meshlines MP-T4 are disposed above the first mesh lines MP-T1 and the secondmesh lines MP-T2. The third mesh lines MP-T3 and the fourth mesh linesMP-T4 are additionally formed on the first mesh lines MPT1 and thesecond mesh lines MP-T2. In this manner, the first mesh lines MP-T1, thesecond mesh lines MP-T2, the third mesh lines MP-T3, and the fourth meshlines MP-T4 are electrically connected to each other. To this end, thethird mesh lines MP-T3 are substantially parallel to the first meshlines MP-T1. The fourth mesh lines MP-T4 are substantially parallel tothe second mesh lines MP-T2. The third mesh lines MP-T3 and the fourthmesh lines MP-T4 may be formed using the same mask as the first meshlines MP-T1 and the second mesh lines MP-T2.

According to one or more exemplary embodiments, the adding part APimproves a density of the conductive portion of the area overlapping thefolding axis FX. As such, the strength of the conductive portion may beimproved and influences exerted on the variation in resistance of thetouch member may be reduced even though the conductive portion ispartially opened via the transmission areas TA. To this end, since thetouch member 20-1 further includes the adding part AP, reliability ofthe touch member 20-1 may be improved, and, as such, a display deviceincluding the touch member 20-1 may have stable electrical performanceregardless of the number of times the display device is folded.

FIGS. 7A and 7B are graphs demonstrating a variation in resistance of atouch member as a function of the number of times the touch member isfolded, according to one or more exemplary embodiments. FIG. 7A showsthe resistance variation of the touch member manipulated into theinwardly folded state, whereas FIG. 7B shows the resistance variation ofthe touch member manipulated into the outwardly folded state.

It is noted that the resistance variations shown in FIGS. 7A and 7B weremeasured with respect to a touch electrode including the mesh lines. Themesh lines may be easily opened (or damaged) due to the folding stress.Although any one of the mesh lines is opened, the electrical signal maybe transmitted through other ones of the mesh lines because the meshlines are electrically connected to each other. However, when the numberof opened mesh lines increases, the number of paths through which theelectrical signal is transmitted is reduced. As such, the resistance ofthe touch member will increase with increasing opened paths in the meshlines. To this end, the variation in resistance may increase as the meshlines are damaged, and the electrical performance may be deteriorated asthe resistance variation increases. The variation in electricalperformance of the touch member, which may be caused, at least in part,by the folding of the touch member, will be described with reference toFIGS. 7A and 7B.

FIG. 7A shows a comparison example PL1 related to mesh lines forming theminimum angle of 90 degrees with respect to the folding axis, a firstembodiment example PL2 related to mesh lines forming the minimum angleof about 40 degrees with respect to the folding axis, and a secondembodiment example PL3 related to mesh lines forming the minimum angleof about 30 degrees with respect to the folding axis.

As previously described, stress caused by folding a display device isstrongest in the direction substantially perpendicular to the foldingaxis and becomes weaker as the direction becomes more parallel to thefolding axis. As seen in FIG. 7A, the resistance variation in thecomparison example PL1 increases rapidly even though the number of timesthe display device is folded is relatively small. Different from thecomparison example PL1, there is almost no variation in the resistancein the first exemplary embodiment example PL2 and the second exemplaryembodiment example PL3 even though the number of times the displaydevice is folded increases. Namely, the resistance variation is about 5%or less. As such, the first exemplary embodiment example PL2 and thesecond exemplary embodiment example PL3 including the mesh lines formingthe minimum angle less than 90 degrees with respect to the folding axisare substantially not influenced due to the folding action.

Similar to the comparison example PL1, as shown in FIG. 7B, theresistance variation in a comparison example PL4 associated with theoutwardly folded state tends to significantly increase when the numberof times the display device is folded increases. The resistancevariation in a first exemplary embodiment example PL5 associated withthe outwardly folded state and in a second exemplary embodiment examplePL6 associated with the outwardly folded state are uniformly representedeven though the number of folding times increases.

Referring to FIGS. 7A and 7B, the resistance variation in the firstexemplary embodiment examples PL2 and PL5 including the mesh linesforming a minimum angle of about 40 degrees with respect to the foldingaxis FX is irregularly represented in association with the outwardlyfolded state as compared to the inwardly folded state. In other words,the plot line associated with the first exemplary embodiment example PL2in FIG. 7A is substantially linear, whereas the plot line associatedwith the first exemplary embodiment example PL5 in FIG. 7B is not aslinear as in FIG. 7A.

As described with reference to FIGS. 3A to 3C, since the touch member 20is farthest away from the folding axis FX when deformed in the outwardlyfolded state, a relatively larger stress deformation occurs inassociation with the outwardly folded state as compared to the inwardlyfolded state. The first exemplary embodiment examples PL2 and PL5including the mesh lines forming a minimum angle of about 40 degreeswith respect to the folding axis are damaged in different degrees inaccordance with the folding state even though the minimum angle isconstant.

Dissimilarly, there is almost no difference in resistance variation inthe second exemplary embodiment examples PL3 and PL6 including the meshlines forming a minimum angle less than about 30 degrees with respect tothe folding axis FX. Accordingly, when the touch member 20 includes themesh lines forming a minimum angle less than about 30 degrees withrespect to the folding axis FX, the electrical performance of the touchmember 20 may be stably maintained despite the folding stress andregardless of the folding direction.

FIGS. 8A and 8B are plan views of touch members, according to variousexemplary embodiments. The touch members in FIGS. 8A and 8B are similarto the touch members in FIGS. 4 and 6A, however, to avoid obscuringexemplary embodiments described herein, primarily differences aredescribed below and duplicative descriptions will be omitted.

Referring to FIG. 8A, a first electrode TE1-1 and a second electrodeTE2-1 forming the touch sensor may be disposed on different layers fromeach other with an insulating layer disposed between the first electrodeTE1 and the second electrode TE2-1. Each of first touch electrodes TE1a-1, TE1 b-1, and TE1 c-1 forming the first electrode TE1-1 includes aplurality of first sensing parts SP1 and a plurality of first connectionparts CP1. The first sensing parts SP1 are arranged in the firstdirection DR1. Each of the first connection parts CP1 extends in thefirst direction DR1 to connect adjacent sensing parts SP1 to each otheramong the first sensing parts SP1. Each of second touch electrodes TE2a-1, TE2 b-1, and TE2 c-1 forming the second electrode TE2-1 includes aplurality of second sensing parts SP2 and a plurality of secondconnection parts CP2. The second sensing parts SP2 are arranged in thesecond direction DR2. Each of the second connection parts CP2 crosses acorresponding first connection part CP1 of the first connection partsCP1. Each of the second connection parts CP2 extends in the seconddirection DR2 to connect adjacent second sensing parts SP2 to each otheramong the second sensing parts SP2.

Furthermore, as seen in FIG. 8A, the folding axis FX may cross oversensing parts (e.g., the first sensing parts SP1) of the touchelectrodes (e.g., the first touch electrodes TE1 a-1, TE1 b-1, and TE1c-1). In this manner, folding stress generated when folding the touchmember 20-2 along the folding axis FX may be distributed over a greaternumber of mesh lines than if the folding axis FX crossed over connectingparts (e.g., the first connecting parts CP1). Although not illustrated,the first sensing parts SP1 overlapping the folding axis FX may includethe adding parts AP of FIG. 6A.

Referring to FIG. 8B, a first electrode TE1-1 and a second electrodeTE2-1 forming the touch sensor may be disposed on the same layer. Forinstance, the second sensing parts SP2 may be disposed on the same layeras the first sensing parts SP1 and may be spaced apart from the firstsensing parts SP1. In this manner, a touch member 20-3 may furtherinclude a plurality of insulating patterns IP to insulate the firstconnection parts CP1 from the second connection parts CP2. Theinsulating patterns IP may be disposed on the same layer as the firstsensing parts SP1 and the second sensing parts SP2 and may overlap thefirst connection parts CP1. To this end, the second connection parts CP2may be disposed on the insulating patterns IP and electrically insulatedfrom the first connection parts CP1. The second connection parts CP2extend outward more than the insulating patterns IP to connect adjacentsecond sensing parts SP2 together. Although not shown, the secondconnection parts CP2 may be connected to the second sensing parts SP2after penetrating through the insulating patterns IP, e.g., through avia or connecting hole formed through the insulating patterns IP.

As with the touch member 20-2 of FIG. 8A, the folding axis FX associatedwith the touch member 20-3 may cross over sensing parts (e.g., the firstsensing parts SP1) of the touch electrodes (e.g., the first touchelectrodes TE1 a-1, TE1 b-1, and TE1 c-1). In this manner, foldingstress generated when folding the touch member 20-3 along the foldingaxis FX may be distributed over a greater number of mesh lines than ifthe folding axis FX crossed over connecting parts (e.g., the firstconnecting parts CP1). Further, although not illustrated, the firstsensing parts SP1 overlapping the folding axis FX may include the addingparts AP of FIG. 6A.

FIGS. 9A and 9B are cross-sectional views of display devices, accordingto various exemplary embodiments. Hereinafter, different layerstructures of display devices will be described with reference to FIGS.9A and 9B.

Referring to FIGS. 9A and 9B, the display member 10 may include a baselayer BS, an element layer El, and an encapsulation layer ECL. The baselayer BS may be formed of any suitable material, such as, for example,various plastic layers having flexibility. For instance, the base layerBS may be formed of polyethylene terephthalate (PET), polyethylenenaphthalate (PEN), polycarbonate (PC), polyethersulfone (PES),polyarylate (PAR), polysulfone (PSF), cyclic-olefin copolymer (COC),polyimide (PI), PI-fluoroalkyl (fluoro) based polymer compound,polyetherimide (PEI), epoxy resin, etc.

The element layer EL is disposed on the base layer BS. As previouslydescribed, the display device may include an organic light emittingdisplay panel as the display member 10. In this manner, the elementlayer EL may include the organic light emitting diode OLED, the thinfilm transistors TFT1 and TFT2, and the capacitor Cap of FIG. 2. Theencapsulation layer ECL is disposed on the base layer BS to cover theelement layer EL. The encapsulating layer ECL may protect the elementlayer EL from moisture, oxygen, debris, contaminants, etc. Theencapsulation layer ECL may include a transparent insulating material.For instance, the encapsulation layer ECL may include at least one of anorganic and inorganic material. To this end, the encapsulation layer ECLmay have a single or multi-layer structure. Furthermore, theencapsulation layer ECL may have a thickness of about 1 micrometer toabout 10 micrometers. In this manner, the display member 10 may beencapsulated by the encapsulation layer ECL, and, as such, the displaydevice may be sufficiently protected, yet slim.

Although not shown, the encapsulation layer ECL may have substantiallythe same thickness as that of the base layer BS. In this manner, asealing member may be further disposed between the encapsulation layerECL and the base layer BS to support the encapsulation layer ECL. It iscontemplated, however, that any suitable structure of the encapsulationlayer ECL may be utilized in association with exemplary embodimentdescribed herein.

As shown in FIG. 9A, the touch member 20 includes a first conductivelayer CL1, an insulating layer IL, and a second conductive layer CL2.Referring to FIG. 4, the first conductive layer CL1 includes the secondelectrode TE2, the second line TW2, and the second pad TP2, and thesecond conductive layer CL2 includes the first electrode TE1, the firstline TW1, and the first pad TP1. In this manner, the touch sensorincluding the first conductive layer CL1 and the second conductive layerCL2 may be directly disposed on the encapsulation layer ECL. The firstconductive layer CL1 may contact an upper surface of the encapsulationlayer ECL. The touch sensor may be disposed directly on theencapsulation layer ECL, and, as such, the display device may be slimmeddown.

As shown in FIG. 9B, the touch member 20-1 may further include a baselayer BL. The base layer BL may be formed of any suitable material, suchas, for example, various plastic materials having flexibility. Forinstance, the base layer BL may include the same material as that of thebase layer BS. Although not shown, an adhesive layer may be furtherdisposed between the base layer BL and the encapsulation layer ECL. Inthis manner, the display device may be manufactured by separatelyforming the touch member 20-1 and the display member 10 and laterdisposing the touch member 20-1 on the display member 10.

According to one or more exemplary embodiments, because the touch member20-1 further includes the base layer BL, reliability of the touch member20-1 may be improved. In addition, given that the touch member 20-1 andthe display member 10 are formed through independent processes, a yieldof the display device may be improved. Further, the display device mayinclude a protection layer PL to further protect the touch member 20-1from external impacts, debris, contaminants, etc. The protection layerPL may be formed of any suitable material, such as one or more organicand/or inorganic materials.

Although certain exemplary embodiments and implementations have beendescribed herein, other embodiments and modifications will be apparentfrom this description.

Accordingly, the inventive concept is not limited to such embodiments,but rather to the broader scope of the presented claims and variousobvious modifications and equivalent arrangements.

What is claimed is:
 1. A display device comprising: a display memberconfigured to generate an image, the display member being, in a planview, divided into: a folding area configured to be folded along afolding axis; and a plan area adjacent to the folding area; and a touchmember configured to detect a touch interaction associated with thedisplay member, the touch member comprising: a touch sensor; and asignal line electrically connected to the touch sensor, wherein thetouch sensor comprises a plurality of touch electrodes, each of theplurality of touch electrodes comprising: first mesh lines extending ina third direction different from the folding axis; and second mesh linesextending in a fourth direction crossing the third direction and beingdifferent from the folding axis and the third direction, wherein one ofthe plurality of touch electrodes overlaps the folding area and furthercomprises: third mesh lines overlapping the folding area, the third meshlines being disposed on the first mesh lines and the second mesh lines;and fourth mesh lines crossing the third mesh lines in the folding area,the fourth mesh lines being disposed on the first mesh lines and thesecond mesh lines, wherein the first mesh lines, the second mesh lines,the third mesh lines, and the fourth mesh lines are electricallyconnected to one another, and wherein at least some of the first tofourth mesh lines overlap the folding axis in the plan view.
 2. Thedisplay device of claim 1, wherein a width of each of the first tofourth mesh lines is greater than or equal to about 10 micrometers andless than or equal to about 3000 micrometers.
 3. The display device ofclaim 2, wherein: the first to fourth mesh lines define transmissionparts; and each transmission part of the transmission parts is apolygonal shape in the plan view.
 4. The display device of claim 3,wherein each of the transmission parts is lozenge shaped.
 5. The displaydevice of claim 3, wherein, in the plan view, different transmissionparts of the transmission parts comprise different polygonal shapes fromone another.
 6. The display device of claim 3, wherein, in the planview, polygonal shapes of the transmission parts are equivalent to oneanother.
 7. The display device of claim 3, wherein: a first transmissionpart of the transmission parts overlaps the folding area; and the firsttransmission part comprises: a first diagonal line substantiallyparallel to the folding axis; and a second diagonal line crossing thefirst diagonal line.
 8. The display device of claim 7, wherein length ofthe first diagonal line is longer than length of the second diagonalline.
 9. The display device of claim 8, wherein the length of the firstdiagonal line is greater than or equal to about 10 micrometers and lessthan or equal to about 500 micrometers.
 10. The display device of claim1, wherein: each of the third mesh lines is substantially parallel toeach of the first mesh lines; and each of the fourth mesh lines issubstantially parallel to each of the second mesh lines.
 11. The displaydevice of claim 1, wherein: the signal line comprises a plurality ofconductive lines; and the plurality of conductive lines define a meshshaped.
 12. The display device of claim 1, wherein: the touch sensorcomprises: a first touch electrode extending in a first direction; and asecond touch electrode insulated from the first touch electrode, thesecond touch electrode extending in a second direction crossing thefirst direction; and each of the first touch electrode and the secondtouch electrode is one of the plurality of touch electrodes.
 13. Thedisplay device of claim 12, wherein: the first touch electrode is one ofa plurality of first touch electrodes; the second touch electrode is oneof a plurality of second touch electrodes; the first touch electrodesextend in the first direction and are arranged in the second direction;and the second touch electrodes extend in the second direction and arearranged in the first direction.
 14. The display device of claim 13,wherein the folding axis extends in a direction substantially parallelto the first direction or the second direction.
 15. The display deviceof claim 12, wherein: the first touch electrode comprises: first sensingparts arranged in the first direction; and first connection partsdisposed between and connecting adjacent first sensing parts of thefirst sensing parts; and the second touch electrode comprises: secondsensing parts arranged in the second direction; and second connectionparts disposed between and connecting adjacent second sensing parts ofthe second sensing parts; each of the first sensing parts and the firstconnecting parts comprises some of the first and second mesh lines ofthe first touch electrode; and each of the second sensing parts and thesecond connecting parts comprises some of the first and second meshlines of the second touch electrode.
 16. The display device of claim 15,wherein: an insulating layer is disposed between the first sensing partsand the second sensing parts; and the insulating layer is disposedbetween the first connection parts and the second connecting parts. 17.The display device of claim 15, wherein: a layer of the touch sensorcomprises the second sensing parts and the first sensing parts; and thesecond sensing parts are, in the plan view, spaced apart from the firstsensing parts.
 18. The display device of claim 1, wherein the displaymember comprises: a base layer; and an element layer disposed on thebase layer, the element layer comprising a light emitting diode.
 19. Thedisplay device of claim 18, wherein: the display member comprises anencapsulation layer covering the element layer; and the touch sensor isdirectly disposed on the encapsulation layer.